The compound forming ccp structure contains $9.6 \times 10^{23}$ atoms. Find the number of tetrahedral voids formed in it.

Identify a pair of molecules having similar shapes of both members.

Calculate the molality of the solution of nonvolatile solute if it freezes at $-0.36^{\circ} \mathrm{C}$.

$\left[K_{\mathrm{f}}\right.$ for solvent $\left.=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$

Calculate $\Delta \mathrm{S}_{\text {Iotal }}$ for a certain reaction if $\Delta \mathrm{H}=-150 \mathrm{~kJ}$ and $\Delta \mathrm{S}=32 \mathrm{JK}^{-1}$ at 300 K .